Pressing jaw, method for producing a non-detachable pipe joint, fitting and system consisting of a pressing jaw and a fitting

ABSTRACT

A cheek plate for producing a non-detachable pipe joint having an upper cheek half and a lower cheek half, at least one swivel pin which pivotally mounts at least one cheek half, and a receiving region formed between the upper cheek half and the lower cheek half and having a receiving region axis, the at least one cheek half being able to pivot between an open position and a closed position substantially transversely with respect to the receiving region axis. The problem of providing a cheek plate such that the cheek plate permits pressing transverse to the receiving region axis and at the same time a reduction in workpiece size is permitted is solved in that at least one pushing unit is provided, the pushing unit being displaceable at least partially in parallel with the receiving region axis.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. patent application Ser. No.14/410,452, filed Mar. 12, 2013, which is the United States nationalphase of International Application No. PCT/EP2013/054996 filed Mar. 12,2013, and claims priority to German Patent Application No. 10 2012 105655.2 filed Jun. 28, 2012, the disclosures of which are herebyincorporated in their entirety by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The invention relates to a pressing jaw for producing a non-detachablepipe joint having an upper jaw half and a lower jaw half, at least onerotation axis which pivotally mounts at least one jaw half, and areceiving region formed between the upper jaw half and the lower jawhalf and having a receiving region axis, whereby the at least one jawhalf is able to pivot between an open position and a closed positionsubstantially transversely to the receiving region axis. The inventionalso relates to a fitting and to a system consisting of a pressing jawaccording to the invention, wherein the fitting comprises a base bodyand a press sleeve. The invention further relates to a method forproducing a non-detachable pipe joint using a pressing jaw and to amethod for joining a fitting to a metallic pipe in metallically sealingmanner.

Description of Related Art

Pressing jaws, fittings, systems and methods of the type mentioned aboveare already known from the prior art, for example from the sectors ofdrinking water installation or heating installation. In this respect, a“non-detachable pipe joint” is understood in particular as meaning thatthe joint is not configured to be detached and reconnected, i.e. it canno longer be detached, or can only be detached with difficulty, inparticular only by destroying the individual workpieces of the pipejoint.

It is intended that the pipe joint can be produced as simply andreliably as possible and will ensure a high degree of tightness for aslong as possible. Pressing jaws or methods are preferably used to pressworkpieces such as fittings, pipes, sockets or the like substantiallyradially, i.e. transversely to the axis of the receiving region. In thisrespect, the receiving region axis extends approximately vertically tothe area spanned between the jaw halves. In the case of a cylindricalreceiving region, the axis of the receiving region substantiallycorresponds to the axis of the cylinder. When a workpiece is introducedinto the receiving region, the receiving region axis and the workpieceaxis of for example a pipe or fitting then substantially coincide, atleast when the jaw halves are closed. The gripper-like closing movementof the jaw halves deforms two or more workpieces, for example a fittingand a pipe, which are arranged such that they at least partly overlap inthe receiving region and as a result are joined together in anon-detachable manner.

For the closing movement of the pressing jaw, a pressing machine isoften used, onto which the pressing jaw is fitted and which pushes abolt or rollers between the rear ends of the jaw halves of the pressingjaw to close the front ends of the jaw halves forming the receivingregion. As an alternative or in addition, for example a manual actuationof the pressing jaw can also be intended. The distinction into “upper”and “lower” (jaw half for example) should not be understood as beingrestrictive. In fact, the pressing jaw can be spatially arranged asrequired.

The prior art pressing procedures can, however, be disadvantageous. Forexample, the exertion of an all-round homogeneous pressing force on theworkpieces to be pressed is made significantly more difficult usingpressing jaws or methods provided for this purpose. Before the pressingprocedure, pipes and fittings preferably have a rotationally-symmetricaland substantially round shape. However, after the pressing procedure,this symmetry can be disturbed due to pressing forces which actnon-homogeneously on the juncture between pipe and fitting, which canimpair the functionality of the joint in particular.

Furthermore, the materials, in particular plastics material or metal, ofthe workpieces which are stressed during the pressing procedure canexhibit inertia towards the pressing forces. This inertia, in the formof restoring forces, can mean that the material, deformed by thepressing procedure, strives to at least partly reproduce the initialstate or the initial structure of the workpieces. This requires the userof a merely radially inwardly acting pressing method to increase thepressing forces to be exerted radially inwards for example, in order toobtain the desired pressing result. However, this represents a demand onthe materials of the workpieces to be pressed which goes beyond theintended extent and thus is basically undesirable.

The previously mentioned problems can be resolved or at least reducedusing a so-called axial pressing method in particular. Here, “axial”means that the workpieces to be pressed are moved at least partly alongthe workpiece axis or the receiving region axis. Although the restoringcharacteristics of the workpieces to be deformed also act in principlein the axial direction, the effects of an increased stress on thematerial due to the usually long axial extent of the workpieces comparedto the radial extent can be minimised.

Pressing tools for an axial pressing of this type are, however, verylarge and bulky since they have to widely encompass the region to beaxially pressed. For this reason, German published patent application DE10 2008 010 083 A1, for example, discloses a method in which a pressingtool for radial pressing can also achieve an axial pressing along thereceiving region axis by means of inclined pressing surfaces on the tooland on the fitting. A fitting can thus be pressed along the receivingregion axis in spite of the movement of the jaw halves transversely tothe receiving region axis.

However, to translate or deflect the pressing force, a particular pathis required which is provided by the inclined surfaces on the outerperipheral surface of the fitting. In this respect, it is a problem thatfittings are required which increase greatly in diameter, because thediameter of the fittings is increased due to the inclined pressingsurfaces. On the one hand, this leads to larger and relativelyunmanageable fittings and on the other hand, it also results in agreater consumption of material, i.e. in higher production costs of thefittings.

The previously described fittings which are to be pressed axiallygenerally use a sealing element consisting of a flexible material, inparticular an elastomer. Likewise, fittings having a seal between twometal workpieces, so-called metallically sealing fittings with axialpressing are known. Before pressing, these fittings to be axiallypressed have radially inwardly projecting cutting edges or ribs which,during pressing, penetrate the material of the pipe to be joined andthereby produce the seal. Thus, the construction of the fittings iscomplex and costly to produce. Fittings of this type are known from U.S.Pat. No. 5,114,191, DE 100 26 083 C1 and DE 101 05 013 C1.

In addition, solder fittings of a very simple construction have beenknown for a long time. Solder fittings consist of a simple section ofpipe, the internal diameter of which is generally the same as that ofthe section of pipe to be joined thereto. At least one end of the solderfitting is widened as a socket over a predetermined receiving portion tosuch an extent that the internal diameter substantially corresponds tothe external diameter of the pipe to be joined. The pipe to be joined isthen inserted into the widened portion, i.e. into the socket and thefitting and the section of pipe are joined in a material-uniting mannerby solder.

For this reason, solder fittings enjoy a wide spectrum of use and are aneconomical alternative to press fittings due to their low productioncosts. Although they are considered to be metallically sealing due tothe solder, solder fittings do not have a material purity because of thedifferent metals of pipe and solder. Furthermore, the fittings have tobe soldered on site in a laborious manner which, on the one hand is verytime-consuming and on the other hand, subject to the surroundings, isnot permitted. Thus, for diverse technical applications, no pressfitting exists which is metallically-sealing, but neverthelesscomparable in economic terms.

SUMMARY OF THE INVENTION

In view of this, the object of the present invention is to provide apressing jaw, a system using a pressing jaw, a method and a fitting, thepressing jaw easily allowing a pressing transversely to the axis of thereceiving region and at the same time allowing a reduction in the sizeof the workpieces, particularly in the size of the fitting.

According to a first teaching of the invention, the technical problem issolved by a generic pressing jaw for producing a non-detachable pipejoint in that at least one pushing unit is provided, said pushing unitbeing displaceable at least partly parallel to the receiving regionaxis.

Due to the fact that the pressing jaw has at least one pushing unitwhich can be displaced at least partly parallel to the receiving regionaxis, with a generic pressing jaw it is easily achieved to allow apressing procedure of the inserted workpiece or workpieces along thereceiving region axis, in spite of a pivoting movement transversely tothe receiving region axis. Hereby, the pushing unit allows the pressingprocedure parallel to the receiving region axis. Here, it is unnecessaryto provide high extending slide surfaces to deflect the force at thefitting, increasing the diameter of the fitting. Instead, the fittingcan be configured with a small diameter, thereby providing aspace-saving fitting which is advantageous to produce due to the savingof material. A workpiece, for example a fitting or a fitting component,can be moved directly by the at least partly parallel movement of thepushing unit parallel to the receiving region axis and relative to atleast one jaw half, without having to provide a force deflection bymeans of slide surfaces on the fitting. Consequently it is also possibleto provide a pressing jaw which is easier to handle compared to axialpressing machines of the prior art. The pressing jaw can also be usedfor pressing workpieces other than fittings.

The expression “displacement at least partly parallel to the receivingregion axis” is understood as meaning that the pushing unit can alsomove in this direction only in portions and/or only temporarily. Inaddition, the pushing unit can perform, for example, a movement at thesame time parallel and transverse to the receiving region axis, so thatat least one component of the movement is parallel to the receivingregion axis. As a result, the pushing unit also thereby moves inparticular at least partly parallel to the workpiece axis which isparallel to or coincides with the receiving region axis. It ispreferable for the pushing unit to be substantially linearlydisplaceable.

The at least one rotation axis for mounting the at least one jaw half(preferably both jaw halves) can preferably be realised using a mountwhich can provide the at least one rotation axis. In this respect, thelower jaw half can also be mounted by a rotation axis which is separatefrom the rotation axis which mounts the upper jaw half. In this respect,the rotation axes are, however, preferably arranged substantiallyparallel.

Since the at least one jaw half can be pivoted about the at least onerotation axis substantially transversely to the receiving region axis,the receiving region axis and the at least one rotation axis aresubstantially parallel.

The workpiece to be pressed is preferably a fitting which preferablyconsists of a base body and a press sleeve which can be pushed onto thebase body. A section of pipe can then be introduced into the fittingbase body, for example. By pushing the press sleeve onto the fittingbase body and/or onto the pipe, a pressing procedure is then carried outparallel to the receiving region axis, i.e. an axial pressing procedureis carried out. A homogeneous, radially inwardly force is exerted on thefitting base body and/or section of pipe by the press sleeve.

According to a configuration of the pressing jaw according to theinvention, the upper jaw half has a first upper jaw quarter and a secondupper jaw quarter and the lower jaw half has a first lower jaw quarterand a second lower jaw quarter. In this respect, the first jaw quarterscan be closed at least partly independently of the second jaw quarters.In other words, the first jaw quarters form a pair of jaws whichconsists of mutually opposite first lower and upper jaw quarters, whilethe second jaw quarters form a pair of jaws which consists of mutuallyopposite second lower and upper jaw quarters. However, the jaw quarterscan also be mounted by at least one common rotation axis. The upper jawquarters, however, are preferably mounted by one rotation axis, whilethe lower jaw quarters are mounted by a further rotation axis. The upperjaw half is preferably constructed mirror-symmetrically to the lower jawhalf, and thus the upper jaw quarters are constructedmirror-symmetrically to the respective lower jaw quarters.

The provision of jaw quarters makes it possible to realise anapplication-specific pressing, i.e. the pressing can be configureddifferently in terms of timing and/or space, for example. Thus, thesecond jaw quarters can be closed time-wise after the first jawquarters, for example. The first and second jaw quarters can also beprovided with different functions by an appropriate configurationthereof. It is also possible to provide more than four jaw parts.

According to a particularly preferred configuration of the pressing jaw,a coupling is provided between the pushing unit and at least one secondjaw quarter, specifically such that the displacement of the pushing unitat least partly parallel to the receiving region axis is at least partlycoupled with the closing movement of the at least one second jawquarter, which takes place substantially transversely to the receivingregion axis.

In this way, the displacement of the pushing unit can be realised in aparticularly simple manner and can be integrated into the closingmovement of the pressing jaw. Thus, no additional actuation, for exampleexternal actuation of the pushing unit is required. Furthermore,pressing machines which are already available and are configured forradial pressing can also be used for axial pressing. A coupling can beachieved, for example, by a mechanical force deflection, so that thepivoting movement of the at least one second jaw quarter, which takesplace substantially transversely to the receiving region axis ortransversely to the at least one rotation axis, causes a displacement ofthe pushing unit at least partly parallel to the receiving region axis.In this respect, the coupling can take place, for example via contactsurfaces, joints and/or by pneumatic means, to list a non-exhaustivenumber of examples. Due to the coupling, the pushing unit and the atleast one first jaw quarter do not have to be of an integralconstruction. The pushing unit is preferably coupled with the secondupper jaw quarter and with the second lower jaw quarter.

The fact that the pushing unit and the at least one second jaw quarterare at least partly coupled means that a coupling can only take place,for example, during the closing movement of the at least one second jawquarter or also only partly during the closing movement. Therefore, thecoupling can be limited time-wise during the pressing procedure. Thusfor example, a closing movement of the at least one second jaw quartercan take place without a displacement of the pushing unit parallel tothe receiving region axis taking place.

Advantageously, the pushing unit is displaced at least partly parallelto the receiving region axis only when the second upper jaw quartermoves relative to the first upper jaw quarter (if a coupling is providedbetween the pushing unit and the upper first jaw quarter) or when thesecond lower jaw quarter moves relative to the first lower jaw quarter(if a coupling is provided between the pushing unit and the lower firstjaw quarter).

According to an advantageous configuration of the pressing jaw, thecoupling is realised by contact surfaces which are provided on thepushing unit and on at least one second jaw quarter, are adapted to oneanother and are inclined relative to the receiving region axis.Consequently, the coupling can be realised in a particularly simple andcost-effective manner. Furthermore, the translation from the closingmovement of the corresponding jaw quarter substantially transversely tothe receiving region axis to the displacement of the pushing unit can beadjusted by the inclination of the contact surfaces.

The mutually adapted contact surfaces are preferably in contact with oneanother during an entire pressing procedure, i.e. when the second jawquarters are open and also when the second jaw quarters are closed, inorder to achieve an efficient transmission of force. The contactsurfaces can advantageously be configured such that they promotesliding.

It has been found that when the contact surfaces are inclined relativeto the receiving region axis by at least 30°, preferably by at least40°, and particularly preferably by at least 45° and/or by a maximum of80°, preferably by a maximum of 70°, particularly preferably by amaximum of 60°, it is possible to achieve a particularly efficienttransmission of force simultaneously with a small-sized pressing jaw.

In this respect, the preferred inclination angle of the contact surfacescan vary subject to the workpieces to be pressed, in particular subjectto the nominal width of the pipes to be pressed. If the inclinationangle is restricted upwards, it is possible to ensure an adequatemovement of the pushing unit parallel to the receiving region axis, i.e.an adequate stroke, during axial pressing. If the inclination angle isrestricted downwards, it is possible to achieve an adequate transmissionof force. Furthermore, in the case of greater inclination angles, a morecompact construction of the pressing jaw can be achieved.

According to a further configuration of the pressing jaw according tothe invention, the second jaw quarters are arranged offset relative tothe first jaw quarters along the receiving region axis. This axialoffset makes it particularly easy to configure the pressing by the firstjaw quarters and/or by the second jaw quarters such that they differ interms of time and/or location, for example.

In this respect, it is advantageous if the first jaw quarters arepositioned substantially in a first plane substantially transversely tothe receiving region axis and if the second jaw quarters are positionedsubstantially in a second plane substantially transversely to thereceiving region axis. In other words, the first and second jaw quartersare located in each case in a radial plane of the receiving region axis.In this manner; in particular the receiving region formed between theupper jaw half and the lower jaw half can be substantially divided intotwo sub-regions, and in the first sub-region, the first jaw quarters canact on the workpiece to be inserted, for example via an inner contour,and in the second sub-region, the second jaw quarters can influence theworkpiece to be inserted, for example via the pushing unit.

In this respect, the concept of the plane is to be interpreted widely,since the jaw quarters not least have a finite extent in the axialdirection, i.e. in the direction of the receiving region axis. In thisrespect, within the meaning of this configuration, the jaw quarterslocated in different planes can also partly overlap and/or engage in oneanother in the direction of the receiving region axis. However, in theregion of the at least one rotation axis and/or in the region ofoptionally provided inlet contours at the rear end of the jaw quarters,the first and second jaw quarters preferably do not overlap in thedirection of the receiving region axis.

If the first jaw quarters are configured as clamping jaws, one or moreworkpieces can be fixed relative to the first jaw quarters. The clampingjaws can fix the workpiece or workpieces particularly in the directionof the receiving region axis, i.e. in the axial direction. The base bodyof a fitting or a section of pipe, for example, can be clamped thus. Inthis respect, the clamping can be achieved both by friction locking andby positive form locking. Likewise, the clamped workpiece or workpiecescan be deformed. As a result of the fixing procedure, a particularlysimple and effective pressing in particular can be achieved by thepushing unit. For example, the workpiece or workpieces to be pressed donot have to be held in position in the direction of the receiving regionaxis by an external force while the pushing unit carries out thepressing procedure in the direction of the receiving region axis.

For this purpose, the first jaw quarters configured as clamping jaws canhave in particular an inner contour which is configured as a clampingprofile and define at least part of the receiving region. This contouris in particular substantially cylindrical and can have for example aribbing or a specific profile for fixing the inserted workpiece.

The first jaw halves are configured in particular such that a closingmovement of said first jaw quarters substantially transversely to thereceiving region axis produces a force substantially transverse to thereceiving region axis, i.e. substantially in an inwardly radialdirection.

In particular in this context, it is particularly preferred if the jawquarters are configured such that the closing movement of the first jawquarters takes place time-wise before the displacement of the pushingunit at least partly parallel to the receiving region axis. Thisensures, for example, that a fitting base body is appropriately fixedbefore a press sleeve, for example, is pushed on by the pushing unit.

A further configuration of the pressing jaw according to the inventionis characterised in that the first jaw quarters have a first inletgeometry and the second jaw quarters have a second inlet geometry, thefirst inlet geometry and the second inlet geometry being configureddifferently. In this way, a temporally adapted movement, in particularthe closing movement of the first and second jaw quarters can beachieved in a particularly simple manner. Thus, for example, a partialor complete closing movement of the first jaw quarters can initially beprovided before the second jaw quarters perform a closing movement.

However, it is particularly preferred if the first jaw quarters are atleast fully closed before the second jaw quarters are fully closed. As aresult, the displacement of the pushing unit at least partly parallel tothe receiving region axis can be offset time-wise to the closingmovement of the first jaw quarters. Consequently, for example aninserted workpiece can initially be clamped or pressed, followedthereafter by a displacement, at least partly parallel to the receivingregion axis, of a further workpiece or of another part of the workpieceby the pushing unit.

If guide means are provided between the pushing unit and at least onefirst jaw quarter so that the movement of the pushing unit substantiallytransversely to the receiving region axis is coupled with the movementof the corresponding at least one first jaw quarter, the pushing unitcan be applied to the workpiece or workpieces to be displaced togetherwith the closing movement of the first jaw quarters. The guide means areprovided particularly in the form of rails and guide bolts which runsubstantially parallel to the receiving region axis and on which thepushing unit can perform a movement parallel to the receiving regionaxis. Thus, particularly when the first jaw quarters are closed, thepushing unit can undergo a displacement which is at least partlyparallel to the receiving region axis. The guide means can also preventthe pushing unit from deviating from a path which the guide means areproviding.

Whereas the movement of the pushing unit transversely to the receivingregion axis is then determined by the first jaw quarters, thedisplacement of the pushing unit substantially parallel to the receivingregion axis is then preferably determined by the second jaw quarters.

It is possible to provide the guide means to be spring-loaded, so thatfor example the pushing unit is automatically returned into the startingposition after the pressing procedure parallel to the receiving regionaxis.

The pushing unit is preferably pushed towards the first jaw quarters, inparticular it is at least partly pushed into a receptable in the firstjaw quarters. In this manner, it is possible to provide a particularlyspace-saving pressing jaw.

According to an advantageous configuration, the pressing jaw ischaracterised in that the pushing unit has an upper pushing element anda lower pushing element. The lower pushing element can thus beassociated with the lower jaw half and the upper pushing element can beassociated with the upper jaw half. In this manner, a homogeneous forcecan also be exerted on the workpiece, for example on a press sleeve,which is to be displaced parallel to the receiving region axis. It isalso possible to provide a pushing unit which has more than two pushingelements.

According to a second teaching of the invention, the object is achievedby a system consisting of a pressing jaw according to the invention anda fitting having a base body and a press sleeve, wherein the receivingregion of the pressing jaw is adapted to the base body of the fittingand wherein the pushing unit of the pressing jaw is adapted to the presssleeve, so that the press sleeve can be at least partly pushed onto thefitting base body by the movement of the pushing unit at least partlyparallel to the receiving region axis.

Due to the provision of a pushing unit which is adapted to the presssleeve, it being possible for the press sleeve to be at least partlypushed onto the fitting base body by the movement of the pushing unit atleast partly parallel to the receiving region axis, in a simple manner asystem is provided, wherein a pressing procedure can be carried out inthe direction of the receiving region axis or of the fitting axis. Here,the axis of the press sleeve, the axis of the fitting base body and thereceiving region axis preferably coincide, at least when the pressingjaw is closed.

In this respect, the pushing unit facilitates the pushing of the presssleeve onto the fitting base body. The press sleeve does not have to bedirectly pushed onto the fitting base body. It is also possible forfurther fitting components or sections of pipe to be provided inbetween.

As a result, high extending slide surfaces on the fitting which increasethe diameter of the fitting do not have to be provided. Instead, thefitting, in particular the press sleeve can be configured with a smalldiameter, thereby making it possible to provide a space-saving fittingwhich is advantageous to produce due to the saving of material.Furthermore, a system can be provided which is easier to handle comparedto the prior art systems.

The pushing unit can be adapted, for example, by radial inwardprojections on the inner contour of the pushing unit which can engagebehind the press sleeve and/or can engage in corresponding recesses. Asan alternative or in addition, radially outwardly engaging projectionscan also be provided on the press sleeve, which projections correspondto the pushing unit.

The pressing jaw is adapted to the base body of the fitting inparticular by an adaption of the first jaw quarters which preferably fixthe base body of the fitting.

With regard to further configurations and advantages of the systemaccording to the invention, reference is made to the subclaims and tothe description of the pressing jaw according to the invention.

According to a third teaching of the invention, the object is achievedby a method for producing a non-detachable pipe joint using a pressingjaw, in particular using a pressing jaw according to the invention,wherein a fitting base body located in a receiving region of thepressing jaw is fixed by actuating the pressing jaw, wherein after thefitting base body has been fixed, the press sleeve is pushed onto thefitting base body by a movement of a pushing unit of the pressing jaw,which movement is at least partly parallel to the receiving region axis.

The method according to the invention allows an axial pressing in asimple manner and, at the same time, a reduction in size of the fitting.The fixing of the fitting base body and the movement of the pushing unitat least partly parallel to the receiving region axis produces an axialpressing, without having to use high extending fittings or massive axialpressing machines.

The section of pipe is advantageously fixed by a first upper and a firstlower quarter of the pressing jaw and the movement of the pushing unit,which is at least partly parallel to the receiving region axis, isproduced by a closing movement of a second lower and a second upperquarter of the pressing jaw. These measures provide a particularlyreliable method which is simple to carry out and allow the use of aparticularly compact pressing jaw.

As set out in more detail below, the previously described method isparticularly suited to the production of a metallically sealing jointbetween a fitting and a section of pipe.

According to a fourth teaching of the present invention, the object setout above is achieved by a fitting for a metallically sealing joint withat least one metallic pipe, having a metal fitting base body and a presssleeve, preferably in the form of a press ring, the fitting base bodyhaving a cylindrical socket with an internal diameter adapted to theexternal diameter of the pipe to be joined, the press sleeve having atone end a receiving portion for receiving an end part of the socket, thepress sleeve having a pressing portion, the inner profile of whichtapers in the axial direction to a diameter smaller than the externaldiameter of the fitting base body, and in a starting position, thefitting base body is partly inserted into the press sleeve and the innerprofile of the pressing portion is capable of tapering the edge of thesocket to an internal diameter which is smaller than the externaldiameter of the pipe to be joined, during an axial displacement onto thefitting base body.

During the pressing procedure, in the case of the fitting according tothe invention, the preferably smooth and burr-free edge of thecylindrical socket of the fitting base body is deformed or flangedradially inwards. This produces a so-called sealing flange. Thus, as aresult of the pressing procedure, the entire periphery of the edge ofthe cylindrical socket becomes a cutting edge. A cutting edge or cuttingrib provided before pressing is thus not required.

Within the context of the present invention, the term “cylinder” or“cylindrical” is understood as meaning a straight cylinder, cylindershaving an area other than a circular shape also being included, inaddition to the most frequently occurring circular cylinders. Theinvention is therefore not restricted to circular-cylindrical fittingbase bodies and pipes.

The described fitting can thus be produced very economically, since onlycomponents of the simplest geometry are required. The installation spacefor a fitting is minimised thereby, as a result of which in particularthe expense of heat insulation after installation can be reduced.

In addition, if the pipe and the fitting base body consist of the samematerial, it is possible to produce a joint made of a single material bypressing. Therefore, the described fitting has a wide field ofapplication, because only the material of the fitting restricts the use.In this respect, copper, stainless steel, galvanised steel, red bronzeas well as suitable plastics materials for example, are possible asmaterials.

The press sleeve of the described fitting is preferably pushed onto thebase body of the fitting such that thereafter, the press sleeve remainson the fitting base body by self-retention without further aids. Forthis purpose, the internal diameter of the inner profile of thereceiving portion can be configured such that a light press fit with thefitting base body is produced. For this purpose, either the internaldiameter can be fully adapted or the inner surface can be roughened. Thepress sleeve can thereby be rigidly connected to the fitting base bodyin the factory, thereby avoiding connection on site.

The receiving portion is preferably cylindrical, so that the socket ofthe fitting base body is received along the cylindrical receivingportion and retained thereon.

It is also possible to configure the receiving portion of the presssleeve such that it tapers, in particular with a conically extendinginner profile at a shallow angle. In this case, the cross section of theopening at the receiving portion of the press sleeve is greater than theexternal diameter of the socket of the fitting base body, whichfacilitates insertion. During insertion, the socket is then guided intothe receiving portion until the press sleeve rests firmly on the socketdue to the tapering cross section of the receiving portion.

In a further preferred manner, the pressing portion has a conical, roundor bulging inner profile. In any case, the inner profile ensures thatwhen the press sleeve is pushed on, the edge of the socket is forcedradially inwards and is thereby flanged. In this respect, theconfiguration as a conically deflecting inner profile is preferred,because this ensures a uniform and continuously performed flanging.However, if the inner contour is round or bulging, then while the presssleeve is being pushed on, the inward gradient increases, so that agreater flanging can be achieved with a shorter displacement path.Furthermore, in this case, the angle at which the edge of the socketcuts into the material of the pipe is steeper.

In a further preferred manner, the angle of the pressing portion to theaxial alignment of the press sleeve and thus to the pipe itself isapproximately 1 to 30°, preferably 10 to 20°. The angle is adapted ineach case to the material which is used and to the proportions in sizeof the fitting base body to be formed and of the pipe wall.

The press sleeve consists of a material which is harder than thematerial of the fitting base body. In particular, the materialpreferably consists of a metal, for example copper, stainless steel,galvanised steel and red bronze. Suitable plastics materials are alsopossible. The surface of the pressing portion preferably consists of thesame material as the press sleeve.

In order to form the socket of the fitting base body in a uniformmanner, it is preferable for the surface of the pressing portion to behardened to ensure that the socket does not cut into the material of thepress sleeve, but assuredly cuts into the material of the pipe, inparticular of the metal pipe. When multilayer pipes are used, the outerlayer usually consists of a plastics material and a layer arranged inthe centre of the composite structure consists of a metal. In this case,a reshaping is necessary inasmuch as a permanent seal is produced by thereshaping of the fitting base body. For this purpose, it may benecessary for the fitting base body to be flanged to such an extent thatthe inner metal layer is also at least partly formed.

If, as mentioned above, the inner profile of the receiving portiontapers, the receiving portion and the pressing portion can extend in auniform inner contour and, for example, can have an identical gradient,at least in the transition region between the two portions. Thus, thereceiving portion and the pressing portion could not be differentiatedfrom one another by a change of the inner contour and could only bedistinguished from one another by their respective functions. Inparticular, the press sleeve can have an inner taper which forms thereceiving portion in the region of the opening and forms the pressingportion adjoining inwardly therewith.

The previously described fitting consisting of base body and presssleeve is suitable for all types of axial pushing tools. Duringpressing, the only significant factor is that the press sleeve is pushedaxially onto the socket of the base body of the fitting. The axialmovement peripherally ensures a uniform flanging of the edge and therebya uniform pressing result.

In particular, the fitting can be pressed by a previously describedpressing jaw with a pushing unit. For this purpose, the fitting basebody preferably has a clamping portion for clamping by means of a firstjaw pair of the pressing jaw. Clamping can be performed with a forcethat the clamping portion is only deformed within the elastic range andafter the pressing jaw has been released, it returns into the startingposition.

However, the clamping action can also result in partial pressing in theregion of the clamping portion, it being possible for the reshaping totake place rotationally symmetrically or also in the form of a polygon,in particular a hexagon to prevent the pipe from twisting relative tothe fitting base body. This reshaping increases the mechanical strengthof the joint, but does not serve to form in a sealing manner.

Furthermore, a pressing procedure using a pressing jaw according to DE10 2008 010 083 A1 is also possible. This type of pressing jaw has apair of jaws which has an oblique contour on both sides of the pressingprofile. Upon compression of the pressing jaw, two engagement surfaces,deflecting at an oblique angle relative to one another, are movedtowards one another, thereby allowing an axial pressing. For thispurpose, the press sleeve has an obliquely deflecting bearing surfaceand the fitting base body has a clamping ring, preferably arranged in acircumferential depression, with a bearing surface extending in theopposite direction.

In a further preferred manner, provided in the fitting base body is aportion which adjoins the socket and has a smaller diameter and servesas a stop in a known manner. Thus, the pipe to be joined can be insertedinto the fitting as far as this stop, so that a satisfactory guidance ofthe pipe through the fitting before pressing is ensured.

A further advantage of the described fitting is that when it is notpressed, it is not tight. In the not yet pressed joint between thesocket of the fitting base body and the pipe, no flexible sealingmaterial can produce an undesired sealing. Thus, when a mounted linewith the fitting according to the invention is tested under pressure, anunpressed fitting is not tight. Only upon completion of axial pressing aseal is produced.

The fittings described above are distinguished by a simple shape which,precisely because of this simplicity, provides a surprisingly goodpressing result for a metallically sealing joint between a fitting and apipe. For this reason, a solder fitting known per se can be used as thefitting base body. Only the press sleeve has to be additionally providedin order to join the solder fitting in a fixed and metallically sealingmanner to an inserted pipe without soldering by axially pushing on thepress sleeve.

The fittings according to the invention can be used in a virtuallyunrestricted manner. On one hand, the fittings can replace knownsolutions with an economical solution, thus for example in the sectorsof drinking water pipe installation and heating pipe installation. Onthe other hand, metallically sealing fittings which are to be pressedaxially based on the present invention can also be used for the firsttime in the following fields of application: refrigeration plants,industrial plants, in particular natural gas pipelines, crude oilpipelines and petrol pipelines as well as chemical industry plants,solar plants, installation plants for conducting medical gases or alsoin the aerospace industry.

According to a fifth teaching of the invention, the object set out aboveis achieved by a method for joining a fitting to a metallic pipe in ametallically sealing manner, in which method a press sleeve having areceiving portion is arranged on a cylindrical socket of a fitting basebody, a pipe is inserted into the cylindrical socket, the press sleeveis pushed axially onto the socket by a pressing jaw, the edge of thesocket is deformed radially inwards by a tapering pressing portionconfigured inside the press sleeve, and the edge of the socket ispressed into the material of the pipe as a cutting edge.

Thus, the method according to the invention can be implementedirrespective of the specific configuration of the pressing jaw. All thatis required is that the pressing jaw and the elements of the fittingsnecessary for the transmission of force are adapted to one another.

With regard to further configurations and advantages of the methodaccording to the invention, the pressing jaw according to the invention,the system according to the invention and the fitting according to theinvention, reference is made to the respective subclaims and to thefollowing description.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following, the invention will be described in more detail withreference to an embodiment illustrated in the drawings, in which:

FIG. 1 is a perspective view of an embodiment of a pressing jaw withopen jaw halves,

FIG. 2 shows the pressing jaw from FIG. 1 with partly closed first jawquarters,

FIG. 3a-c are different views of the pressing jaw from FIG. 2 withclosed first jaw quarters,

FIG. 4a-c are different views of the pressing jaw from FIG. 3 withadditionally closed second jaw quarters,

FIG. 5 is a perspective view of the pressing jaw from FIG. 1 with openjaw halves, also with a fitting,

FIG. 6a-c are different views of the pressing jaw and the fitting fromFIG. 5 with a fully inserted fitting and closed first jaw quarters,

FIG. 7a-c are different views of the pressing jaw with fitting from FIG.6 with closed second jaw quarters,

FIG. 8 is a perspective view of a first embodiment of a fittingaccording to the invention before pressing,

FIG. 9 is a cross-sectional view of the fitting from FIG. 8,

FIG. 10 is a perspective view of the first embodiment of a fittingaccording to the invention after pressing,

FIG. 11 is a cross-sectional view of the fitting from FIG. 10,

FIG. 12 is a cross-sectional view of a second embodiment of a fittingaccording to the invention before pressing,

FIG. 13 is a cross-sectional view of the fitting from FIG. 12 afterpressing,

FIG. 14a-d show different configurations of the inner profile of a presssleeve according to the invention,

FIG. 15 is a perspective view of a third embodiment of a fittingaccording to the invention before pressing,

FIG. 16 is a cross-sectional view of the fitting from FIG. 14 withapplied pressing jaw,

FIG. 17 is a perspective view of the third embodiment of a fittingaccording to the invention after pressing, and

FIG. 18 is a cross-sectional view of the fitting from FIG. 16.

DETAILED DESCRIPTION OF THE INVENTION

In the following, a pressing jaw 1, a system and a method according tothe present invention will be described by way of example with referenceto FIGS. 1 to 7. FIGS. 8 to 18 show embodiments of fittings according tothe invention.

FIG. 1 is a perspective view of an embodiment of a pressing jaw 1 withopen jaw halves 2 a, 2 b. The upper jaw half 2 a of the pressing jaw 1consists of a first upper jaw quarter 4 a and a second upper jaw quarter6 a. The lower jaw half 2 b consists of a first lower jaw quarter 4 band a second lower jaw quarter 6 b. In FIG. 1, the pressing jaw 1 isshown with open jaw halves 2 a, 2 b, i.e. both the first jaw quarters 4a, 4 b and the second jaw quarters 6 a, 6 b are in a fully openposition. The mount 8 has an upper rotation axis 8 a which pivotallymounts the upper jaw quarters 4 a, 6 a, and a lower rotation axis 8 bwhich pivotally mounts the lower jaw quarters 4 b, 6 b.

The first jaw quarters 4 a, 4 b each have a rear end 10 a, 10 b whichform an inlet geometry 12 for a pressing machine. Likewise, the rearends 14 a, 14 b of the second jaw quarters 6 a, 6 b form an inletgeometry 16 for the pressing machine. A receiving region 22 is formedbetween the front ends 18 a, 18 b of the first jaw quarters 4 a, 4 b andthe front ends 20 a, 20 b of the second jaw quarters 6 a, 6 b. Thereceiving region 22 has a receiving region axis 24. The receiving regionaxis 24 runs substantially parallel to the rotation axes 8 a and 8 b ofthe mount 8. As a result, the first jaw quarters 4 a, 4 b and the secondjaw quarters 6 a, 6 b arranged offset along the receiving region axiscan each be pivoted in a plane transversely to the receiving region axis24 and transversely to the rotation axes 8 a, 8 b.

The pressing jaw 1 also comprises a pushing unit 26 which has an upperpushing element 26 a and a lower pushing element 26 b. The upper pushingelement 26 a of the pushing unit 26 is connected to the first upper jawquarter 4 a by the guide means 28 a. The lower pushing element 26 b isconnected to the first lower jaw quarter 4 b by the guide means 28 b.The guide means 28 a, 28 b are configured as guide rails or guide boltswhich run substantially parallel to the receiving region axis 24. Thepushing elements 26 a, 26 b can be moved into corresponding receptables30 a, 30 b of the first jaw quarters 4 a, 4 b by the guide means 28 a,28 b. In FIG. 1, the pushing unit 26 is shown in the position moved outof the first jaw quarters 4 a, 4 b.

A coupling 32 a is provided between the upper pushing element 26 a ofthe pushing unit 26 and the second upper jaw quarter 6 a, while acoupling 32 b is provided between the lower pushing element 26 b of thepushing unit 26 and the second lower jaw quarter 6 b. In the illustratedembodiment, the couplings 32 a, 32 b are realised in each case asmutually adapted contact surfaces 34 a, 34 b, 36 a, 36 b on the pushingelements 26 a, 26 b of the pushing unit 26 and on the second jawquarters 6 a; 6 b. In this respect, the contact surface 34 a arranged onthe upper pushing element 26 a is in contact with the contact surface 36a of the second upper jaw quarter 6 a, while the contact surface 34 barranged on the lower pushing element 26 b is in contact with thecontact surface 36 b of the second upper jaw quarter 6 b. Due to thecouplings 32 a, 32 b, the displacement of the pushing unit 26,substantially parallel to the receiving region axis 24, is partlycoupled with the closing movement of the second jaw quarters 6 a, 6 bsubstantially transversely to the receiving region axis 24, as willbecome apparent from the further figures.

The receiving region 22 is substantially divided in two. The innercontour 38 of the first jaw quarters 4 a, 4 b which delimits thereceiving region 22 and is provided with a clamping profile forms afirst sub-region in which a workpiece, in particular a fitting base bodycan be clamped or fixed, in the direction of the receiving region axis.In the second sub-region of the receiving region 22, which secondsub-region is delimited by the pushing elements 26 a, 26 b of thepushing unit 26, a workpiece, in particular a press sleeve can be movedby the pushing unit 26 parallel to the receiving region axis 24 orworkpiece axis. The pushing unit 26 has a suitably adapted inner contour40 for this purpose.

FIG. 2 shows the pressing jaw 1 from FIG. 1 with partly closed first jawquarters 2 a, 2 b. In this state, the pressing jaw 1 can be applied inparticular to one or more workpieces without a clamping and/or pressingprocedure having started. By pushing apart the rear ends 10 a, 10 b,forming the inlet geometry 12, of the first jaw quarters 4 a, 4 b, thefirst jaw quarters 4 a, 4 b are almost completely closed. In thisrespect, the inlet geometry 16 of the second jaw quarters 6 a, 6 b isconfigured similarly to the inlet geometry 12 of the first jaw quarters4 a, 4 b in the vicinity of the rear ends 14 a, 14 b of the second jawquarters 6 a, 6 b. Consequently, the second jaw quarters 6 a, 6 b arealso closed initially parallel to the first jaw quarters 4 a, 4 b. Thesecond upper jaw quarter 6 a and the first upper jaw quarter 4 a havethereby not moved relative to one another. The same applies to the lowerjaw quarters 4 b, 6 b. This can also be recognised, inter alia, from thefact that, as shown in FIG. 1, the second jaw quarters 6 a, 6 b havestill not engaged in the provided recesses 41 a, 41 b in the first jawquarters 4 a, 4 b.

Due to the movement of the first jaw quarters 4 a, 4 b substantiallytransversely to the receiving region axis 24, the pushing elements 26 a,26 b have also been moved accordingly substantially transversely to thereceiving region axis 24. In this respect, the second upper jaw quarter6 a and the upper pushing element 26 a also have the same positionrelative to one another. The same applies accordingly to the secondlower jaw quarter 6 b and the lower pushing element 26 b. Thus, thepushing unit 26 has not been moved in the direction of the receivingregion axis 24.

FIG. 3a-c are different views of the pressing jaw 1 from FIG. 2 withclosed first jaw quarters 4 a, 4 b. First of all, FIG. 3a is aperspective view. In contrast to FIG. 2, the first jaw quarters 4 a, 4 bare now fully closed. The front ends 18 a, 18 b of the first jawquarters 4 a, 4 b as well as the pushing elements 26 a, 26 b are lyingon top of each other. The inner contour 38 of the first jaw quarters 4a, 4 b and the inner contour 40 of the pushing unit 26 form a receivingregion 22 which is closed in the circumferential direction.

The side view depicted in FIG. 3b shows that the receiving region 24 hasa substantially circular cross section. However, elliptical or polygonalcross sections, for example, are also possible.

The inlet geometry 16 of the second jaw quarters 6 a, 6 b tapers in thedirection of the front end 20 a, 20 b of the second jaw quarters 6 a, 6b more narrowly compared to the inlet geometry 12 of the first jawquarters 4 a, 4 b. Due to the different inlet geometries 12, 16, apressing machine can close the second jaw quarters 6 a, 6 b in atime-delayed manner with respect to the first jaw quarters 4 a, 4 b.

FIG. 3c shows a cross section along line IIIc from FIG. 3b through thefront ends 18 a, 18 b, 20 a, 20 b of the jaw quarters 4 a, 4 b, 6 a, 6 bin the region of the receiving region 22. The second jaw quarters 6 a, 6b are opened further than the first jaw quarters 4 a, 4 b which arealready fully closed. Compared to FIG. 1, the pushing elements 26 a, 26b have not yet been moved parallel to the receiving region axis 24. Thepushing unit 26 is at a distance from the first jaw quarters 4 a, 4 b.The contact surfaces 34 a, 34 b of the pushing elements 26 a and 26 bare already in contact with the corresponding contact surfaces 36 a and36 b of the second jaw quarters 6 a and 6 b. The contact surfaces 34 a,34 b, 36 a, 36 b have an angle of approximately 50° to the receivingregion axis 24.

FIG. 4a-c show the pressing jaw 1 from FIG. 3 in a view analogous toFIG. 3, but also with closed second jaw quarters 6 a, 6 b, FIG. 4a is aperspective view of the pressing jaw 1, while FIG. 4b shows a side view.In contrast to FIG. 3, the second jaw quarters 6 a, 6 b are now alsofully closed due to a further movement transversely to the receivingregion axis 24. This can be recognised, inter alia, from the ends 14 a,14 b which have now been pushed further apart, of the second jawquarters 6 a, 6 b. As a result, the front ends 20 a, 20 b now engage inthe recesses 41 a, 41 b provided in the first jaw quarters 4 a, 4 b. Dueto the closing movement of the second jaw quarters 6 a, 6 bsubstantially transversely to the receiving region axis 24, the secondjaw quarters 6 a, 6 b move relative to the corresponding first jawquarters 4 a, 4 b. Consequently, the contact surface 34 a of the upperpushing element 26 a slides along the contact surface 36 a of the secondupper jaw quarter 6 a and the contact surface 34 b of the lower pushingelement 26 b slides along the contact surface 36 b of the second lowerjaw quarter 6 b. Since the pushing elements 26 a, 26 b of the pushingunit 26 do not have any freedom of movement transversely to thereceiving region axis 24 due to the guide means 28 a, 28 b, a movementof the pushing elements 26 a, 26 b parallel to the receiving region axis24 into the receptables 30 a, 30 b results from the coupling between thesecond jaw quarters 6 a, 6 b and the pushing elements 26 a, 26 b.

FIG. 4c shows, analogously to FIG. 3c , a cross section along line IVcfrom FIG. 4b . In contrast to FIG. 3c , the pushing elements 26 a, 26 bof the pushing unit 26 are now arrested against the first jaw quarters 4a, 4 b, since the pushing elements 26 a, 26 b have been moved towardsthe first jaw quarters 4 a, 4 b along the guide means 28 a, 28 b by theclosing movement of the second jaw quarters 6 a, 6 b transversely to thereceiving region axis.

FIG. 5 shows, inter alia, the pressing jaw from FIG. 1. With regard tothe description of the pressing jaw 1, reference is made to FIGS. 1 to4. In contrast to FIG. 1, FIG. 5 also shows a workpiece in the form of afitting 50. The fitting 50 comprises a fitting base body 54 and twopress sleeves 56 and 58 attached to the fitting base body. The fitting50 is substantially tubular. In the open position of the jaw halves 2 a,2 b, the fitting 50 having the axis 52 can be introduced into thereceiving region 22 transversely to the receiving region axis 24.

Analogously to FIG. 3a-c , FIG. 6a-c are different views of the pressingjaw 1 and of the fitting 50 from FIG. 5 with closed first jaw quarters 4a, 4 b. When the first jaw quarters 4 a, 4 b are closed, the axis 52 ofthe fitting 50 coincides with the receiving region axis 24. The innercontour 38 of the first jaw quarters 4 a, 4 b is adapted to the outerperipheral surface of the base body 54 of the fitting 50. Therefore, inthe closed position of the first jaw quarters 4 a, 4 b, the innercontour 38 clamps the base body 54. In this respect, the fitting basebody 54 can also be pressed transversely to the workpiece axis 52.However, only a clamping action preferably takes place, so that thefitting base body 54 is secured relative to the pressing jaw 1 againstmovements in the direction of the workpiece axis 52 or in the directionof the receiving region axis 24.

In the position of the pushing element 26 shown in FIG. 6a-c , thepushing unit 26 engages behind the press sleeve 56. The pushing unit 26is adapted by radial inward projections 44 a, 44 b of the upper andlower pushing elements 26 a and 26 b on the inner contour 40 of thepushing unit 26, which projections 44 a, 44 b engage behind the presssleeve 56.

If the second jaw quarters 6 a, 6 b are now moved into their closedposition transversely to the receiving region axis 24, due to thecoupling 32 a, 32 b the pushing unit 26 is moved substantially parallelto the receiving region axis 24, as a result of which the press sleeve56 is pushed onto the fitting base body in the direction of the axis 52of the fitting 50. As a result, for example a pipe (not shown) insertedinto the fitting 50 can be pressed with the fitting 50.

This state is shown in FIG. 7a-c which are different views of thepressing jaw 1 with fitting 50 from FIG. 6 with closed second jawquarters 6 a, 6 b, analogously to FIG. 4a -c.

The press sleeve 58 which, as can be seen in FIG. 7c , is still onlypositioned can then be pushed onto the fitting base body 54 by thepressing jaw 1 in the same manner as the press sleeve 56 by introducingthe fitting 50, rotating it by 180°, into the receiving region 22.

FIGS. 7a and 7b also show a pressing machine 70. By introducing therollers 70 a, 70 b between the rear ends 10 a, 10 b and 14 a, 14 b whichform the inlet geometries 12, 16, the pressing jaw is gradually closed.In the position of the pressing jaw 1 shown in FIG. 7, the pressing jawis already completely closed, i.e. the rollers 70 a, 70 b of thepressing machine 70 have moved in to such an extent that the first jawquarters 4 a, 4 b as well as the second jaw quarters 6 a, 6 b are fullyclosed.

Thereafter, all the jaw quarters 4 a, 4 b; 6 a, 6 b can be openedtogether, for example by hand and the pressing jaw 1 can be removed fromthe pressed fitting 50 which can produce a non-detachable pipe joint.

Fittings according to the invention will be described in more detail inthe following with reference to FIGS. 8 to 18.

FIGS. 8 to 11 illustrate a first embodiment of a fitting 50 according tothe invention, in a perspective view and in a cross-sectional view ineach case.

The fitting 50 is provided for a metallically sealing joint with atleast one metallic pipe 80. A metallic fitting base body 54 has acylindrical socket 82 with an internal diameter which is adapted to theexternal diameter of the pipe 80 to be joined. The illustrated end ofthe pipe 80 can thereby be inserted into the socket 82 in order to thenbe joined to the fitting base body 54.

Furthermore, a press sleeve 56 in the form of a press ring is providedat the end shown to the left-hand side of the fitting base body 54.Provided at the other end of the fitting base body 54 is also a socket84 which cooperates in the same way with the press sleeve 58 and thepipe 80 as the socket 82 cooperates with the press sleeve 56 and thepipe 80. For this reason, only socket 82 and the mode of operationthereof will be described in the following.

At one end, the press sleeve 56 has a receiving portion 86 for receivingan end part of the socket 82. The press sleeve 56 can thereby be partlypushed onto the socket 82 in order to achieve a satisfactory retentionat the same time as accurately positioning the press sleeve 56 relativeto the socket 82. In the starting position shown in FIGS. 8 and 9, thefitting base body 54 has thus been partly inserted into the press sleeve56. In this respect, it is preferred that the inner contour of thereceiving portion 86 produces a self-retention when the press sleeve 56has been positioned on the socket 82. For this purpose, the internaldiameter can be selected such that a light press fit with the socket 82is produced. Likewise, the inner contour of the receiving portion 86 canbe provided with a roughened surface to produce the self-retentioneffect.

Furthermore, the press sleeve 56 has a pressing portion 88, the innerprofile of which tapers in the axial direction to a diameter smallerthan the external diameter of the fitting base body 54. The innerprofile of the pressing portion 88 is thus capable of tapering the edgeof the socket 82 to an internal diameter which is smaller than theexternal diameter of the pipe 80 to be joined, during an axialdisplacement onto the fitting base body 54.

This state is shown in FIGS. 10 and 11. The socket 82, inserted into thepress sleeve 56, of the fitting base body 56 is formed or flangedradially inwards so that the edge of the socket 82 cuts into thematerial of the pipe 80. Formed thereby over the entire circumference ofthe socket 82 is a cutting edge 89 in the form of a sealing flange whichproduces a metallically sealing joint between fitting base body 54 andpipe 80.

The straight edge of the cylindrical fitting 50 or of the cylindricalsocket 82 is thus reshaped into a circumferential cutting edge 89 by thepressing procedure.

The previously described mode of operation of the fitting base body 54,shown on the left-hand side, with socket 82 in cooperation with thepress sleeve 36 and the pipe 80 applies likewise to the socket 84, presssleeve 58 and pipe 80, shown on, the right-hand side.

FIG. 12 (not pressed) and FIG. 13 (pressed) show a second embodiment ofa fitting 50 according to the invention, in which the fitting base body54 is only provided at one end with a socket 54 and a press sleeve 56,whereas the end shown on the right-hand side is configured as aninsertion end 90. In this respect, the shape of the fitting base body isillustrated as being straight. In addition, curved arcs, T pieces orarmatures are also possible as the fitting base body.

As shown in FIGS. 8 to 13, the receiving portion 86 is cylindrical.Therefore, the socket 82 can be positioned accurately due to the axialguidance of the receiving portion 86, thereby allowing a good, uniformpressing result to be obtained.

Furthermore, the pressing portion 88 is conical, as also shown in FIGS.8 to 11. As a result, a uniform reshaping of the end of the socket 82 isachieved. A circumferential edge 87 then runs between the receivingportion 86 and the pressing portion 88.

FIG. 14 shows a plurality of possible inner contours of the press sleeve56, the receiving portion 86 and the pressing portion 88 havingdifferent contours.

FIG. 14a shows the inner contour from FIGS. 8 to 13, where the receivingportion 86 is cylindrical and the pressing portion 88 is conical.

FIG. 14b shows an inner contour with an overall conical path with thesame gradient for the receiving portion 86 and for the pressing portion88, so that these two portions cannot be directly differentiated fromone another. Therefore, in a uniformly deflecting inner contour, a firstportion is designated as the receiving portion 86 and the adjoiningportion is designated as the pressing portion 88, the respectiveportions assuming the respective functions. The flat gradient makes itpossible for the receiving portion 86 to receive the socket (not shownhere) in a self-retaining manner, so that the press sleeve 54 can bepre-installed on the fitting base body (not shown here).

In FIG. 14c , the receiving portion 86 is again cylindrical, whereas thepressing portion 88 is round or bulging. The distinction between roundand bulging depends on which radial path is selected for the curvedinner contour of the pressing portion 88.

Finally, FIG. 14d shows a press sleeve 54, in which both the receivingportion 86 and the pressing portion 88 have a curved inner contour inthe axial direction. An inserted socket is thereby initially guided intothe press sleeve being progressively inserted, and is then increasinglyshaped inwards.

In the illustrated embodiments, the conical surfaces are shown at anangle to the axial direction. In this respect, the preferred angularrange is from 1 to 30°, in particular from 10 to 20°.

The fitting shown in FIGS. 8 to 13 is suitable for axial pressing usinga pressing jaw according to the invention which has been described inconnection with FIGS. 1 to 7. The pressing procedure can be seenparticularly in FIGS. 5, 6 c and 7 c.

For this purpose, the fitting base body 54 has a clamping portion 92 forclamping by means of a first jaw pair 4 a, 4 b of the pressing jawdescribed above. The clamping portion 92 adjoins the portion of thefitting base body 54 which has been inserted into the press sleeve 56.

Clamping by means of the jaw pair 4 a, 4 b axially fixes the fittingbase body 54 together with the pipe 80 so that it is subsequentlypossible to push the press sleeve 56 onto the fitting base body 54. Forthis reason, first of all the fitting base body 54 is fixed and onlythen is the press sleeve 56 pressed on axially.

The pressing jaws 4 a, 4 b can also produce a partial pressing of theclamping portion 92, i.e. a partially permanent forming of a structureinto the fitting base body 54. In this respect, pressing can be carriedout rotationally symmetrically or also in the form of a polygon, inparticular a hexagon to prevent the pipe 80 from twisting relative tothe fitting base body 54. Although the pressing in the region of theclamping portion 92 increases the mechanical strength of the joint, itdoes not replace the axial pressing of the press sleeve 56 onto thefitting base body 54.

As already mentioned, the pressing procedure of the described fitting 50is not restricted to the use of the pressing jaws according to theinvention. Any other form of axial pressing can be used for the fitting50 according to the invention.

An example of this is shown in FIGS. 15 to 18 as a third embodiment,where the same reference numerals are used for the same elements of thefitting 50 as before. For this reason, reference is made only to thedifferences compared to the previously described embodiments.

The third embodiment is capable of being pressed axially by a pressingjaw, as described in DE 10 2008 010 083 A1.

The press sleeve 56 which has been pushed onto the fitting base body 54in the starting position has an obliquely deflecting bearing surface 94.Furthermore, the fitting base body 54 has a clamping ring 98, arrangedin a circumferential depression 96, with a bearing surface 100, thealignment of which runs in an opposite direction to the bearing surface94. The clamping ring 98 is at least partly flexible so that it can bepositioned on the metal fitting base body 54. Nevertheless, the clampingring 98 is sufficiently resistant to be able to provide the function ofan abutment for the axial pressing forces, as is described in thefollowing.

FIG. 16 shows, in addition to a fitting 50, a pressing jaw 102 which hastwo bearing surfaces 104 and 106 which are aligned in oppositedirections to one another. Bearing surface 104 cooperates with bearingsurface 94 of the press sleeve 56, whereas bearing surface 106 restsagainst bearing surface 100 of the clamping ring 98.

An identically configured pressing jaw 108 with bearing surfaces 110 and112 rests on the opposite side of the press sleeve 56 and, in this case,bearing surface 110 interacts with bearing surface 94 of the presssleeve 56 and bearing surface 112 interacts with bearing surface 100 ofthe clamping ring 98.

During pressing, the two pressing jaws 102 and 108 are moved towards oneanother and the oblique bearing surfaces slide along one another, as aresult of which the press sleeve 56 is pressed onto the fitting basebody 54. In this respect, the clamping ring 98 acts as an abutment.FIGS. 17 and 18 show the pressed state of the press sleeve 56.

FIGS. 15 to 18 show a respective second press sleeve 58, as in FIGS. 8to 11. The press sleeve 58 also has an obliquely deflecting bearingsurface and the clamping ring 98 also has a bearing surfacecorresponding thereto. Therefore, the press sleeve 98 can also beaxially pressed by means of the clamping ring 98 and the describedpressing jaws 102 and 108 when they have been applied accordingly.

The fitting base bodies 54, shown in FIGS. 8 to 13 and 15 to 18 can beconfigured as a solder fitting, for example. These fittings which areeconomical to produce can therefore be easily axially pressed in ametallically sealing manner by the present invention.

Finally, in the illustrated embodiments, a stop for the pipe 80 to beinserted is formed in the fitting base body 54 by a circumferentialdepression 114, by a shoulder 116 or by the depression 96 for theclamping ring 98.

The invention claimed is:
 1. A fitting for a metallically sealing jointwith at least one metallic pipe, comprising a metal fitting base bodyand a press sleeve, wherein the metal fitting base body has acylindrical socket with an internal diameter adapted to an externaldiameter of the pipe to be joined, wherein the press sleeve has at oneend a receiving portion for receiving an outermost end of thecylindrical socket, wherein the press sleeve has a pressing portion, aninner profile of which tapers in an axial direction to a diametersmaller than an external diameter of the metal fitting base body, suchthat the inner profile of the pressing portion is configured during anaxial displacement onto the metal fitting base body to deform theoutermost end of the cylindrical socket radially inwards so that theoutermost end of the cylindrical socket cuts into material of the pipe,wherein in a starting position, the metal fitting base body is partlyinserted into the press sleeve, wherein the press sleeve furthercomprises an outer obliquely deflecting bearing surface and the metalfitting base body further has an outer clamping ring being secured andrecessed in a longitudinally centralized groove in the fitting base bodyand the clamping ring has an outer bearing surface which runs in anopposite direction to the bearing surface of the press sleeve, andwherein a longitudinal space is maintained between the clamping ring andthe press sleeve.
 2. The fitting according to claim 1, wherein thereceiving portion is cylindrical or is configured tapering.
 3. Thefitting according to claim 1, wherein the pressing portion has aconical, round or bulging inner profile.
 4. The fitting according toclaim 1 wherein the metal fitting base body has a clamping portion forclamping by means of a first pair of jaws of a pressing jaw.
 5. Thefitting according to claim 1, wherein the metal fitting base bodycomprises a section of pipe, an internal diameter of which is the sameas a section of the pipe to be joined thereto, and wherein the metalfitting base body comprises at least one end widened as a socket over apredetermined receiving portion to an extent that an internal diameterof the receiving portion corresponds to an external diameter of the pipeto be joined.